Physics of auroral phenomena : proceedings of the 35th Annual seminar, Apatity, 28 Februaru – 02 March, 2012 / [ed. board: A. G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2012. - 187 с. : ил., табл.
О.M. Barkhatova et al. as the background (zero) level. Remaining disturbances were divided into classes which assign a value from 1 to 4. Each new class correspond an increase in XL intensity for 3 times. Thus has been obtained a new parameter CXL (classificated XL). Classification of geomagnetic field horizontal component was carried out by a procedure similar to the classification of ionospheric disturbance [Barkhatova et al., 2011; velvet and Barkhatova, 2012]. For this the maximal and minimal values of the horizontal component in the international quiet and disturbed days for 1975 and 1982 was determined. On the basis of these values assigned 7 classes of magnetic disturbance and a new parameter CMF (classificated MF) which characterizes the current magnetic disturbances at observed station. Table 1 shows the range of values for each of the received parameters. Table 1. Helio-geophysical parameter Range of parameter values Index values AE AE < 500 0 500 < AE < 800 1 800 < A E < 1100 2 1100 < A E < 1400 3 AE> 1400 4 XL XL < 0 0 0 < XL < 0.1*10'5 1 0.1*10-5 < XL < 0.340 s 2 0.3*10'5< XL < 0.9Ч0'5 3 XL > 0.9*10'5 4 MF -10.5 < MF <16 0 16 < MF < 25 1 - 1 5 <MF< 10.5 -1 25 < MF < 40 2 -47 <MF < -15 -2 MF > 40 3 -80 < MF < -47 -3 MF < -80 -4 2. Estimation of the Solar-magnetospheric parameters impact on index IAI Before direct assessment of the effects of each parameter on the index IAI, it is essential to delete all regular events from the values of each index because that can be superimposed on the desired effect and distort them. The phenomenon of terminator passage can not be removed from the index IAI values within procedure of its creation because the time of sunrise varies depending on the season. To observe the effect o f the terminator passage the daily sunrise at station Moscow by Solar zenith angle values was determined. Next we consider the time interval from 2 hours before sunrise and 2 hours after. For each hour of the interval was conducted summary values IAI during the year (Figure 1). £ 1 Д] Moskow 4S0 van 300f lb*) Ш 110i ioo-j VO 0f i л о i i Sunrise |« ш Dim из/? mvm Dim ssioso a im ei»w| Fig. 1. Histogram of summary values IAI versus time before (negative values) and after (positive) pass the terminator through the station Moscow from 1975 to 1982. On x-axis are conditional hours ("0" corresponds to the sun rising above the horizon), the y-axis - the total value of the index IAI for the year Analysis of the results presented in Fig. 1 shows that the greatest values the total annual index IAI receives at sunrise. This result can be considered as successful demonstration of the influence of the terminator passage on ionospheric disturbances. To correct the observed effect of the index data IAI was produced subtracting the contribtion of disturbance caused by terminator passage. Next was searched a relationship between index IAI disturbances and disturbances of indexed Solar-magnetospheric parameters and assessed the level of these relations. To do this, the index IAI compared with indexed values of parameters (CAE, CMF, CXL). The coincidence of thought disturbances found in the case when both parameters are non-zero. To quantify description of connection 104
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